A fuel cell is a cell for directly converting chemical energy, generated by the oxidation of fuel, into electrical energy.
Most of fuel cells use hydrogen as fuel. However, the use of a fuel cell using hydrogen in the state in which the supply system of hydrogen fuel has not been constructed as it is now is limited.
Accordingly, there is a need for a transitional system that generates hydrogen by prereforming carbonate hydrogen-based fuel and uses the hydrogen as fuel. For this reason, a fuel cell system that is now being developed is equipped with such a prereformer.
The methanation of carbonate hydrogen series that belong to carbonate hydrogen series and that have a carbon number of 2 (C2) or higher other than CH4, hydrogen conversion, etc. are performed through the prereformer. Accordingly, a reduction in the performance of a fuel cell stack attributable to coking generated when C2 or higher is introduced into the fuel cell stack can be prevented. Furthermore, produced hydrogen gas maintains a reduction atmosphere within the fuel cell stack, and functions as a controller in thermal management. Furthermore, if some oxidants are introduced, the produced hydrogen gas functions as an oxidizer, and is responsible for a buffer that collects sulfur when the sulfur is introduced and protects the fuel cell stack.
A steam reforming reaction, that is, a main reaction of the prereformer, is a heat absorption reaction, and there is a case where the temperature conditions of gas supplied to the anode are not satisfied. To this end, there is a need for a structure for satisfying the temperature conditions.